// 标签页面
<template>
  <div class="tags"
       v-if="showTags">
    <ul>
      <li class="tags-li"
          @contextmenu.prevent="openMenu($event,item,index)"
          v-for="(item,index) in tagsList"
          :class="{'active': isActive(item.path)}"
          :key="index">
        <router-link :to="item.path"
                     class="tags-li-title">
          {{item.title}}
        </router-link>
        <span class="tags-li-icon"
              @click="closeTags(index)"><i class="el-icon-close"></i></span>
      </li>
    </ul>

    <div class="tags-close-box">
      <el-dropdown @command="handleTags">
        <el-button size="mini"
                   type="primary">
          标签选项<i class="el-icon-arrow-down el-icon--right"></i>
        </el-button>
        <el-dropdown-menu size="small"
                          slot="dropdown">
          <el-dropdown-item command="other">关闭其他</el-dropdown-item>
          <el-dropdown-item command="all">关闭所有</el-dropdown-item>
        </el-dropdown-menu>
      </el-dropdown>
    </div>

    <div class="floatTag"
         style="position:absolute;z-index:999;"
         :style="{'margin-left':left+'px'}"
         v-if="visible">
      <ul class="contextmenu">
        <li @click="refreshCurrentTab(item)">刷新</li>
        <li @click="closeCurrentTab(item)">关闭当前</li>
      </ul>
    </div>
  </div>
</template>

<script>
import bus from '../../utils/bus'
export default {
  data () {
    return {
      tagsList: [],
      visible: false,
      top: 0,
      left: 0,
      // 左侧菜单栏折叠标志
      collapse: false,
      // 当前有击的标签
      curretTagIndex: ''
    }
  },
  computed: {
    showTags () {
      return this.tagsList.length > 0
    }
  },
  watch: {
    // 是否展示发生变化
    visible (value) {
      if (value) {
        document.body.addEventListener('click', this.closeMenu)
      } else {
        document.body.removeEventListener('click', this.closeMenu)
      }
    },
    $route (newValue, oldValue) {
      this.setTags(newValue)
    }
  },
  methods: {
    isActive (path) {
      return path === this.$route.fullPath
    },
    // 关闭单个标签
    closeTags (index) {
      const delItem = this.tagsList.splice(index, 1)[0]
      const item = this.tagsList[index] ? this.tagsList[index] : this.tagsList[index - 1]
      if (item) {
        delItem.path === this.$route.fullPath && this.$router.push(item.path)
      } else {
        this.$router.push('/back/dashboard')
      }
    },
    // 关闭全部标签
    closeAll () {
      this.tagsList = []
      let item = {
        name: 'dashboard',
        path: '/back/dashboard',
        title: '系统首页'
      }
      this.tagsList.push(item)
      // this.$router.push('/back/dashboard')
    },
    // 关闭其他标签
    closeOther () {
      const curItem = this.tagsList.filter(item => {
        return item.path === this.$route.fullPath
      })
      this.tagsList = curItem
    },
    // 设置标签
    setTags (route) {
      const isExist = this.tagsList.some(item => {
        return item.path === route.fullPath
      })
      if (!isExist) {
        if (this.tagsList.length >= 8) {
          this.tagsList.shift()
        }
        this.tagsList.push({
          title: route.meta.title,
          path: route.fullPath,
          name: route.matched[1].components.default.name
        })
      }
      bus.$emit('tags', this.tagsList)
    },
    handleTags (command) {
      command === 'other' ? this.closeOther() : this.closeAll()
    },
    // 刷新当前页面
    refreshCurrentTab (item) {
      this.$router.go(0)
    },
    // 关闭当前页签
    closeCurrentTab (item) {
      this.closeTags(this.curretTagIndex)
    },
    // 打开右键标签时候的菜单
    openMenu (e, item, index) {
      this.curretTagIndex = index
      var x = e.pageX
      var y = e.pageY
      this.top = y
      this.left = x
      if (!this.collapse) {
        this.left = this.left - 250
      } else {
        this.left = this.left - 64
      }
      this.visible = true
    },
    closeMenu () {
      this.visible = false
    }

  },

  created () {
    this.setTags(this.$route)
    // 监听关闭当前页面的标签页
    bus.$on('close_current_tags', () => {
      for (let i = 0, len = this.tagsList.length; i < len; i++) {
        const item = this.tagsList[i]
        if (item.path === this.$route.fullPath) {
          if (i < len - 1) {
            this.$router.push(this.tagsList[i + 1].path)
          } else if (i > 0) {
            this.$router.push(this.tagsList[i - 1].path)
          } else {
            this.$router.push('/')
          }
          this.tagsList.splice(i, 1)
          break
        }
      }
    })
    // 左侧是否折叠
    bus.$on('collapse', msg => {
      this.collapse = msg
    })
  }
}

</script>

<style>
.tags {
  /* position: relative; */
  height: 30px;
  overflow: hidden;
  background: #fff;
  padding-right: 120px;
  box-shadow: 0 5px 10px #ddd;
}

.tags ul {
  box-sizing: border-box;
  width: 100%;
  height: 100%;
}

.tags-li {
  float: left;
  margin: 3px 1px 2px 3px;
  border-radius: 3px;
  font-size: 12px;
  overflow: hidden;
  cursor: pointer;
  height: 23px;
  line-height: 23px;
  border: 1px solid #e9eaec;
  background: #fff;
  padding: 0 5px 0 12px;
  vertical-align: middle;
  color: #666;
  -webkit-transition: all 0.3s ease-in;
  -moz-transition: all 0.3s ease-in;
  transition: all 0.3s ease-in;
}

.tags-li:not(.active):hover {
  background: #f8f8f8;
}

.tags-li.active {
  color: #fff;
}

.tags-li-title {
  float: left;
  max-width: 80px;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
  margin-right: 5px;
  color: #666;
}

.tags-li.active .tags-li-title {
  color: #fff;
}

.tags-close-box {
  position: absolute;
  right: 0;
  top: 0;
  box-sizing: border-box;
  padding-top: 1px;
  text-align: center;
  width: 110px;
  height: 30px;
  background: #fff;
  box-shadow: -3px 0 15px 3px rgba(0, 0, 0, 0.1);
  z-index: 10;
}

.contextmenu {
  margin: 0;
  background: #409eff;
  list-style-type: none;
  padding: 5px 0;
  border-radius: 4px;
  font-size: 12px;
  font-weight: 400;
  color: rgb(255, 255, 255);
  box-shadow: 2px 2px 3px 0 rgba(0, 0, 0, 0.3);
}

.contextmenu li {
  width: 50px;
  margin: 0;
  padding: 2px 2px;
}

.contextmenu li:hover {
  background: rgb(182, 181, 181);
}
</style>
